Controlling MS Word via COleDispatchDriver

I have an app which controls MS Word 97 via COleDispatchDriver. The problem is that "winword.exe" stays in memory (abnormally long, I checked it with Task Manager) although I use COleDispatchDriver::ReleaseDispatch().
I've also tried the following simple code snippet which leads to the same problem.

Word conforms to the Automation specifications for servers that implement a user interface. There are various problems of having a UI in an automation server due to reference counting and such. So in order to get around these problems, Word still stays in memory even when you release its IDispatch interface. The correct way of closing down Word is to call the Application's Quit method and then releasing the interface.